Next time let them know the procedure can kill if/when done wrong. Problems range from scarring to the point it can look like STDs to the general public, to entire loss of the penis, to blood loss leading to death. That's the kind of person your sister in law chose to be through ignorance or otherwise, someone who potentially put the life of her newborn at risk because she's likely a shitty person and hypocrite when it comes to these things, as Stonetoss repeatedly highlights:

https://i2.wp.com/stonetoss.com/wp-content/uploads/2018/07/consent-and-circumcision-comic1.png?fit=625%2C605

https://i1.wp.com/stonetoss.com/wp-content/uploads/2019/05/my-body-my-choice-comic.png?fit=1500%2C500

https://i0.wp.com/stonetoss.com/wp-content/uploads/2018/10/baby-gender-circumcision-comic.png?fit=1500%2C500

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